Analogue Wormholes and Black Hole LASER Effect in Hydrodynamics

TL;DR

This paper demonstrates the existence of traversable and bi-directional analogue wormholes in fluid dynamics, showing how water wave dispersion allows for LASER-like trapping of negative energy between multiple horizons, unlike in general relativity.

Contribution

It introduces the concept of analogue wormholes and LASER effects in hydrodynamics with complex flow profiles and multiple dispersive scales, expanding previous models.

Findings

Traversable and bi-directional analogue wormholes are possible in water flows.

Negative energy can be trapped between horizons forming a LASER-like cavity.

Six horizons are involved due to two dispersive scales, unlike previous models.

Abstract

We numerically study water wave packets on a spatially varying counter-current in the presence of surface tension. Depending on the details of the velocity profile, we show that traversable and bi-directional analogue wormholes exist in fluid mechanics. The limitations on traversability of wormholes in general relativity are absent here because of the dispersion of water waves and the ability to form flow profiles that are not solutions of Einstein's equations. We observe that negative energy can be trapped between analogue horizons forming a LASER-like cavity. Six horizons are involved in the trapping cavity because of the existence of two dispersive scales, in contrast to previous treatments which considered two horizons and one dispersive scale.